Numerous formulations have been developed as alternative fuels to replace the conventional fossil-based fuels. An example of such a fuel is disclosed in Canadian patent 1340871, in which alcohol is mixed with ether and a lubricant such as mineral oil or a vegetable oil, such as castor oil. Formulations have also been developed for use as alternative fuels that combine renewable carbon sources such as alcohols with fossil fuels. An example of such a fuel is disclosed in Canadian patent 2513001, in which alcohol is mixed with naptha and an aliphatic ester. Similarly, U.S. Pat. No. 4,300,912 discloses a synthetic fuel formulation comprising naptha (20-60%), methanol (10-40%), butanol (20-40%) and a colloidal stabilizer that is prepared by heating the formulation in a reactor to a temperature of 300° Fahrenheit then passing the resulting vapors through a water cooled condenser and collecting the liquid fuel in a holding tank. U.S. Pat. No. 5,575,822 discloses a number of fuel and fuel additives. The fuels range from two component formulations, such as 10 to about 42% terpene, preferably limonene, and from about 1 to about 90% naphtha compound to more complex formulations such as 10 to about 16 w/w % limonene, from about 19 w/w % to about 45 w/w % aliphatic hydrocarbons having a flash point between 7° C., to about 24° C., most preferably Varnish Makers and Painters (VM&P) naptha, from about 20 w/w % to about 40% w/w % alcohol, most preferably methanol, from about 9 w/w % to about 36 w/w % surfactant, most preferably glycol ether EB and a preferred fuel comprising about 11.4 w/w % limonene, about 40.7 w/w % VM&P naptha, about 15.5 w/w % glycol ether EB, about 22 w/w % methanol, and about 10.6 w/w % castor oil. Such formulations require significant fuel delivery system modifications. Formulations using methanol degrade conventional fuel lines and seals, such as O rings. Furthermore methanol is corrosive and castor oil, when mixed with methanol, forms deposits within fuel injectors and carburetors that reduce the lifespan of the parts and lead to undue maintenance costs. Also, the relatively high flash point of VM&P naptha results in poor cold starts.
Whitworth's U.S. Pat. Nos. 4,818,250 and 4,915,707 describe a process for purifying limonene for use as a fuel or fuel additive. The process includes distillation of limonene-containing oil followed by removal of water. The distilled limonene, blended with an oxidation inhibitor such as p-phenylenediamine, is claimed as a gasoline extender when added in amounts up to 20% volume. Unfortunately, in actual testing under a power load in a dynamometer, addition of 20% limonene to unleaded 87 octane gasoline resulted in serious preignition, casting serious questions as to its practical value as a gasoline extender.
Terpenoid-based fuels have been disclosed in U.S. Pat. No. 5,186,722. Disclosed are a very wide range of terpenes, terpenoids and derivatives thereof, including limonenes, menthols, linalools, terpinenes, camphenes and carenes. The fuels are produced by a cracking/reduction process or by irradiation. Limonene was shown to produce 84% 1-methyl-4-(1-methylethyl) benzene by this process. While the fuel is superior to that of Whitworth, production costs are relatively high.
Eucalyptus oil was explored by Barton and coworkers as a fuel additive. Barton and Knight (1997, Chemistry in Australia 64 (1): 4-6) identified commercial solvents and Barton and Tjandra (1988, Fluid phase eqilibria 44:117-123, 1989, Fuel 68:11-17) identified stabilization of petroleum/ethanol fuel blends as potential uses for cineole (from eucalyptus oil). It functions as a co-solvent in fuel blends comprising polar and nonpolar components (petroleum and ethanol for example), thereby preventing phase separation. Cineole is the major component of eucalyptus oil, comprising about 80% of the oil. In other studies, eucalyptus oil was used as a fuel. Performance was very good except that there were problems starting a cold engine on straight eucalyptus oil, which could be readily overcome by adding 20 to 30% alcohol or gasoline.
Various vegetable oils have been added to fuel formulations to increase the lubricity value. For example, U.S. Pat. No. 5,730,029 discloses using peanut oil, and other oils having high (80%) oleic acid content, in two-stroke fuels. The combination of a high lubricity value and a high flash point allows for lubrication at high engine temperatures. The flame retarding characteristic of the oil assists in increasing power. U.S. Pat. No. 5,743,923 disclose using peanut oil in conjunction with an alcohol and a petroleum fractional distillate.
U.S. patent application Ser. No. 10/506,963 discloses a fuel additive that is an emulsifying composition that includes a selected ethoxylated alkylphenol, which functions as a surfactant, a fatty acid amide, naphtha and oleic acid. The preferred composition includes one part polyoxyethylene-nonylphenol, two parts coconut diethanolamide, two parts heavy naphtha and one part oleic acid, by volume. The invention also extends to a hydrocarbon fuel including the composition.
Despite the foregoing, a composition has not been provided that compares favourably to existing fuels with regard to horsepower and BTU output, for use in spark ignition engines (two stroke, four stroke and jet engines), in the absence of hardware or software modifications. It is an object to overcome the deficiencies of the prior art.